angular - mat-form-field must contain a MatFormFieldControl

Question

We are trying to build our own form-field-Components at our Company. We are trying to wrap material design's Components like this:

field:

<mat-form-field>
    <ng-content></ng-content>
    <mat-hint align="start"><strong>{{hint}}</strong> </mat-hint>
    <mat-hint align="end">{{message.value.length}} / 256</mat-hint>
    <mat-error>This field is required</mat-error>
</mat-form-field>

textbox:

<field hint="hint">
    <input matInput 
    [placeholder]="placeholder" 
    [value]="value"
    (change)="onChange($event)" 
    (keydown)="onKeydown($event)" 
    (keyup)="onKeyup($event)" 
    (keypress)="onKeypress($event)">
</field>

Usage:

<textbox value="test" hint="my hint"></textbox>

This results in approximately this:

    <textbox  placeholder="Personnummer/samordningsnummer" value="" ng-reflect-placeholder="Personnummer/samordningsnummer">
       <field>
          <mat-form-field class="mat-input-container mat-form-field>
             <div class="mat-input-wrapper mat-form-field-wrapper">
                <div class="mat-input-flex mat-form-field-flex">
                   <div class="mat-input-infix mat-form-field-infix">
                      <input _ngcontent-c4="" class="mat-input-element mat-form-field-autofill-control" matinput="" ng-reflect-placeholder="Personnummer/samordningsnummer" ng-reflect-value="" id="mat-input-2" placeholder="Personnummer/samordningsnummer" aria-invalid="false">
                      <span class="mat-input-placeholder-wrapper mat-form-field-placeholder-wrapper"></span>
                   </div>
                </div>
                <div class="mat-input-underline mat-form-field-underline">
                   <span class="mat-input-ripple mat-form-field-ripple"></span>
                </div>
                <div class="mat-input-subscript-wrapper mat-form-field-subscript-wrapper"></div>
             </div>
          </mat-form-field>
       </field>
    </textbox>

But I'm getting "mat-form-field must contain a MatFormFieldControl" in the console. I guess this has to do with mat-form-field not directly containing a matInput-field. But it is containing it, it's just withing the ng-content projection.

Here is a blitz: https://stackblitz.com/edit/angular-xpvwzf

Answer 1

I had this issue. I imported MatFormFieldModule at my main module, but forgot to add MatInputModule to the imports array, like so:

import { MatFormFieldModule, MatInputModule } from '@angular/material';

@NgModule({
    imports: [
        MatFormFieldModule,
        MatInputModule
    ]
})
export class AppModule { }

More info here.